One Laptop Per Child organization is considering to dump x86 architecture microprocessors in favour of ARM architecture chips or even ARM-based system-on-chip designs in the next-generation XO laptop aimed at developing nations. While this could potentially trim costs and boost power consumption, this also means lack of compatibility with desktop Microsoft Windows operating system (OS).

“We’re seeing some very impressive system-on-chip (SoC) designs that provide both fundamentally low-power demands and the kind of fine-grained power management in the XO-1. Our current XO-1 uses an average of 5W of power, and while most people think that’s amazingly low, we think it’s our biggest problem,” said Ed McNierney, chief technology officer at OLPC, in an interview with IDG News Service.

There are a lot of low-power x86 microprocessors on the market nowadays: both Advanced Micro Devices and Intel Corp. now offer relatively high-performance chips with low thermal envelope. However, ARM processors consume even less and there is a number of promising SoC designs, such as Nvidia Tegra with DirectX 9-class programmable graphics core inside an ARM-based SoC, that consume even less with no apparent drawbacks.

But ARM processors do bring a problem for OLPC’s XO-2: the lack of compatibility with Windows operating system for desktops. In addition, over time OLPC will have to ensure software availability for the XO-2, which will hardly be easy to achieve if the system is not based on an x86 microprocessor.

“Like many, we are urging Microsoft to make Windows – not Windows Mobile – available on the ARM. This is a complex question for them,” said Nicholas Negroponte, the head of non-profit OLPC organization.

The OLPC XO-2 is expected to include a software-designed, touch-sensitive keyboard and two touch-screen displays, according to reports.

Besides improving software support and ensuring low power consumption, OLPC also has to integrate support of 3G or WiMAX connectivity into the XO-2 in order to provide Internet access in rural areas.